Defines a class with a custom metaclass to customize class creation behavior.

Declares a class that uses a custom metaclass to customize class creation, enabling frameworks or custom behavior.

When you need to intercept class creation for ORMs, frameworks, automatic registration, validation, or attribute injection.

Object-oriented programming, metaprogramming, Python frameworks such as Django models, ORMs, plugin systems.

class <ClassName>(metaclass=<MetaClass>):

class definition with metaclass argument

ClassName MetaClass

• class metaclass Meta type

• MyClass MyMeta

forgetting to inherit from type when defining a custom metaclass missing parentheses around metaclass argument confusing metaclass with inheritance

class MyClass: class MyClass(Base): class MyClass(metaclass=type):

Confusing metaclass syntax with inheritance or decorator syntax Assuming metaclass is inherited by subclasses automatically

• class definition
• metaclass
• descriptor
• property

The metaclass must be a subclass of type; it receives the class name, bases, and namespace as arguments.

Signals that class creation will be customized, allowing frameworks to inject behavior or attributes.

Think of a metaclass as a class factory that creates classes.

Advanced metaclass patterns (e.g., automatic registration, validation)